This invention relates to a cartridge configured to be inserted into a meter.
Diabetes sufferers may be provided with quantities of insulin, for instance by injection, sometimes a number of times daily. The quantity of insulin that is appropriate depends on the person's blood glucose level, so blood glucose level measurement can also occur a number of times daily.
Blood glucose level measurement typically is a multi stage process. The first is lancing, in which a lancet, or needle, is used to pierce the skin of a user, for example on the end or side of a finger. Once a suitable amount of blood has been produced, a sample is taken on a testing strip. A person may need to squeeze their finger in order to cause sufficient blood to be expelled. Sometimes lancing needs to be reperformed. The testing strip then is provided to a meter, typically an electronic meter, which analyses the sample, for example by determining a parameter (e.g. an electrochemical potential or voltage, resulting from a chemical reaction between the blood sample and an enzyme present in the testing strip, and provides a blood glucose measurement result. This measurement is then used to determine an amount of insulin to be consumed by the person.
Unpublished PCT patent applications numbered PCT/EP2011/061536, PCT/EP2011/061537, PCT/EP2011/061538, PCT/EP2011/061540 and PCT/EP2011/061542 and European application numbers EP11182381.1, EP11182383.7 and EP11190679.8 relate to a new class of blood glucose measurement device. The device includes lancing and measuring features. In use, a user places a body part against an aperture in the device and the device first lances the body part then collects a blood sample, then processes the blood sample to measure a blood glucose level.
A first aspect of the invention provides a cartridge configured to be inserted into a meter, the cartridge comprising:
wherein when the seal is in a sealed condition the seal is secured to the exterior side wall of the cartridge by a non-permanent adhesive, and a part of the seal covers the aperture so as to provide a moisture impermeable barrier, and the knob is located adjacent the side wall of the housing.
The cartridge may have a protrusion formed on the sidewall, the protrusion being coincident with the knob when the seal is in the sealed position. The protrusion may have a longitudinal axis that extends substantially parallel to a longitudinal axis of the cartridge. This can provide an arrangement that is particularly intuitive for a user to operate in the sense that the movement of the knob required to move the seal is guided to occur in a direction in which the user would expect to need to move the knob. Moreover, this can be achieved whilst allowing the protrusion to act as a guide member for inserting the cartridge into a meter.
The protrusion may extend to a position coincident with the junction between the sidewall and the end face of the cartridge housing. This can provide a particularly convenient form for the cartridge.
The knob may be connected to the protrusion by a temporary fixing. This can assist retaining of the knob in the desired location
The knob may have a groove formed within a face that face faces the sidewall of the cartridge when the seal is in the sealed condition.
The groove may have a longitudinal axis that extends substantially parallel to a longitudinal axis of the cartridge. This can help to ensure that the knob, and thus the seal, remains in place in the sealed position prior to intentional removal of the seal by a user. Furthermore, it can allow the protrusion to have a corresponding orientation, thus allowing it to serve as an orientation guide when inserting the cartridge into a meter.
The protrusion and the groove may have complementary cross-sections. For example, the protrusion and the groove may have generally triangular cross-sections, and/or the protrusion and the groove may have generally rounded cross-sections.
When the seal is in the sealed position, an end part of the knob, for example a part of the knob that is furthest from the aperture, may be located coincident with the junction between the sidewall and the end face of the cartridge housing. This can provide a particularly convenient form for the cartridge. Additionally, providing the know on a corner of the cartridge housing can allow relatively easy gripping of the knob by a user, potentially facilitating removal of the seal when required without compromising resistance of the seal to accidental removal.
The knob may have a face that slopes downwards from a maximum radial height of the knob in the axial direction parallel to the longitudinal axis of the cartridge towards the location of the aperture. This can provide a convenient face against which a user can exert a force when removing the seal from the cartridge. Here, the face that slopes downwards from a maximum radial height of the knob towards the location of the aperture is curved such that it is steeper in the radial direction as the distance from the aperture increases. This can provide an even more convenient face against which a user can exert a force when removing the seal from the cartridge.
The seal has a longitudinal axis that extends substantially parallel to a longitudinal axis of the cartridge.
The invention also provides a system comprising a meter having a housing and a cartridge as above, wherein the housing of the meter is configured to allow the cartridge to be inserted therein only after removal of the knob.
Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
a is a perspective view of the cartridge with a seal partly removed and indicating a location of the seal when in a sealed position;
b is the same as
c is an end view of the cartridge with the seal in place; and
A blood glucose meter (BGM) 100 is shown in
On one side face of the BGM are provided first, second and third inputs 101, 102, 103. These may take the form of push-switches or touch sensitive transducers, for instance. Also provided on the side of the BGM next to the input devices 101 to 103 is a display 104. This may take any suitable form, for instance a liquid crystal display (LCD), e-ink etc. In use, a user may control the BGM 100 using the input devices 101 to 103 and may be provided with information by the BGM through the display 104.
Located at a front face of the BGM 100 is an aperture 105. The aperture 105 is located at approximately half of the height of the BGM. The aperture 105 is configured such as to be able to receive a part of a user's body, for the purpose of extracting a blood sample therefrom. For instance, the aperture 105 may be dimensioned so as to receive an end or a side part of a finger or thumb, or may be dimensioned so as to receive a side of a user's hand or a pinch of skin from a user's arm. The aperture may be rectangular in shape. Its edges may be bevelled, so as to guide a user's digit into a specific location.
The aperture 105 is provided in the side of a cartridge 106. The cartridge has a generally cylindrical form, and is arranged vertically in the BGM 100.
In particular, the BGM includes a first housing part 107. The first housing part 107 forms the base, left and right side face and the rear face of the BGM 100. On the front face of the BGM 100, the first housing part 107 also comprises the lowermost part of the side face. A fixed lid part 108 is attached to the first housing part 107. The fixed lid part 108 comprises most of the top surface of the BGM 100. A removable lid part 109 comprises the remaining part of the top surface of the BGM 100. The removable lid part is disposed above the cartridge 106 at the front face of the BGM 100.
The first housing part 107 is configured such as to provide an elongate aperture 110 at the front face of the BGM 100. The elongate aperture 110 may extend for most of the height of the front face of the BGM 100. The elongate aperture 110 is defined at the uppermost part by the removable lid part 109 and is defined by the first housing part 107 at the right, left and bottom. The BGM 100 is arranged such that the cartridge 106 occupies the whole of the area of the elongate aperture 110. A slidable or pivotable door in the housing part 107 of the BGM 100 may cover all or a part of the elongate aperture 110 when the BGM is not in use. The door may cover at least the aperture 105, such as to prevent the ingress of dirt and other potential contaminants into the aperture 105
The cartridge 106 is more clearly visible in
In
The removable lid part 109 is configured such that when removed from the BGM 100 the cartridge 106 is able to be extracted from the BGM by moving it vertically along its axis. In
In
Formed with the inner surface of the hollow cylindrical housing part 203 are first and second guide members 205, 206. In
A bus 211 is arranged to connect a number of components including a microprocessor 212, random access memory (RAM) 213, read-only memory (ROM) 214, a keys interface 215, a display driver 216, an analyte interface circuit 219 and a motor interface 217. All of these components are powered by a battery 218, which may take any suitable form.
Stored in the ROM 214 is software and firmware that governs operation of the blood glucose meter 100. The software/firmware is executed by the microprocessor 212 using the RAM 213. The software/firmware stored in the ROM 214 is operable to operate the blood glucose meter 100 such as to allow control by a user through the keys or input devices 101 to 103, as detected by the keys interface 215. A blood glucose measurement and other information is provided on the display 104 at suitable times by operation of the software/firmware and the microprocessor 212 through the display driver 216.
The motor interface 217 allows the microprocessor 212, according to the software/firmware stored in the ROM 214, to control the motor that is coupled to the drive wheel 201, and any other motors that are included in the blood glucose meter 100 (as will be described below).
The analyte interface circuit 219 is operable to provide electrical signals with certain voltages to the electrical contact terminals 401, and thus the contact pads 318 and thus the analyte measuring part 316, and to measure parameters of signals such as to allow the microprocessor 212 to measure a blood glucose level of a blood sample.
Mounted on the shaft 204 are a plurality of members, three of which are shown in
One test disc member 208 is shown in some detail in
The test disc member 208 includes an uppermost surface 303, a lowermost surface 304, which is shown in
A hole 306 is formed at the centre of the test disc member 208. The hole 306 comprises two main parts. A circular part is centred on the test disc member 208 and has a diameter equal to or slightly larger than the external diameter of the shaft 204. A drive notch 307 abuts the circular part of the hole 306 and includes edges that are able to be engaged by a drive dog.
A drive dog 320 (visible in part in
On the underside of the test disc member 208 is provided a spacer member 308. The spacer member 308 comprises a slice of a hollow cylinder. The cylinder is centred on the centre of the test disc member 208. The inner diameter of the spacer member 308 is selected such that the hole 306 does not overlap with the spacer member 308. The outer diameter of the spacer member 308 is only slightly greater than the inner diameter, so the spacer member 308 has little thickness. The height of the spacer member 308 is between 0.5 and 1 millimetre. When plural test disc members are stacked together, the spacer member 308 provides separation between the upper surface 303 of one test disc member and the lower surface 304 of the test disc member that is directly above it. The separation is determined by the height of the spacer member 308.
Referring again to
Located next to the third position 314 is a blood collection part 315. This may take any suitable form. For instance, it may comprise a laminated material. The blood collection portion 315 has the function of drawing blood that is in contact with the disc edge 305 at the third position into the test disc member 208 to an blood analyte measuring part 316, that adjoins the blood collection part 315, for example a part containing an enzyme for blood glucose measuring, or the like. Blood may be drawn through capillary action. The analyte measuring part 316 includes an enzyme that reacts chemically with blood in such a way that blood glucose level can be measured. The analyte measuring part 316 is connected to first to third contact pads 318 by first to third conductive tracks 317. The contact pads 318 and the conductive tracks 317 are formed on the upper surface 303 of the test disc member 208. The analyte measuring part 316 also is formed on the upper surface 303 of the test disc member 208. Some or all of the conductive tracks 317, the contact pads 318 and the analyte measuring part 316 may be printed onto the upper surface 303 of the test disc member 208.
As will be described in detail below, in use a part of a user is firstly pierced by the lancet 309, the part is then milked by the disc edge 305 at the cutaway portion 302, and blood then is provided to the analyte measuring part 316 through the blood collecting portion 315. A measuring circuit connected to the analyte measuring part 316 by way of the conductive tracks 317 and the contact pads 318 then is able to determine a blood glucose level of the user. The level then is displayed on the display 104.
Operation will now be described with reference to the figures.
As shown in
At the position shown in
From the position shown in
The test disc member 208 continues to rotate until the blood collection portion 315 is aligned with the aperture 105. Here, rotation ceases. At this location, blood that has been caused to be expelled from the user's digit by the lancet 309 and by action of the disc edge 305 on the user's digit is caused to be drawn to the analyte measuring part 316 by capillary action. The blood and the enzyme then react.
At a suitable time, the shaft 204 is caused to be rotated further in an anticlockwise direction. Here, the test disc member 208 is caused to be rotated from the position shown in
When the first test disc member 208 moves upwards, between
By virtue of movement up the cartridge 106 of the first to third test disc members 208 to 210, the third guide member 207 ceases to be within the notch 301 of the second test disc member 209. At this stage, the third guide member 207 does not prevent rotational movement of the second disc member 209.
At the position shown in
By providing a stack of test disc members 208 to 210 within the cartridge 106 and by providing a suitable physical arrangement, a cartridge 106 can be used for multiple tests. When the cartridge 106 is new, the test disc members 208 to 210 are located in the bottom half of the cartridge 106, with the uppermost test disc member being aligned with the aperture 105. As test disc members are used, the stack of test disc members moves upwards in the cartridge. When the last test disc member is used, the cartridge can be said to be spent. At this stage, all of the test disc members are located in the uppermost portion of the cartridge 106.
It will be appreciated that the number of test disc members 208 to 210 that can be accommodated within the cartridge 106, and thus the number of tests that can be provided by a cartridge 106, is a factor of the height of the cartridge 106, and the separation between corresponding parts (e.g. the upper surfaces) of adjacent test disc members 208 to 210. A taller cartridge and/or a reduced separation of test disc members increases the number of tests that can be performed using a single cartridge 106.
Reference will now be made to
Referring firstly to
The slit aperture 400 does not coincide with the elongate aperture 110 that is formed at the front side of the BGM 100. As such, the slit aperture 400 is not visible when the cartridge 106 is in place within the BGM 100.
Adjacent to the slit aperture 400 is located a swing arm 401. The swing arm 401 is rotatable about a spindle 402, as shown in
Mounted on the swing arm 401 are first to third electrical contact terminals 405. Each includes a generally horizontal arm 405a and a depending contact head 405b. The electrical contact terminals 405 are made of a resilient conductive material, for instance metal. The depending contact heads 405b are angled at their ends furthest from the swing arm 401.
In one position, shown in
The connecting arm 403 is controlled to remain in a position shown in
Alternatively or additionally, each of the conductive contacts 318 may be generally concentric with the shaft 402 for at least a part of their length. This can allow the plural terminals 405 to remain in contact with their respective conductive contacts 318 while the member rotates. Thus, for instance, the test disc member 208 could be rotated away from the position in which the blood analysis part is exposed to collect a blood sample whilst allowing the plural terminals 405 to remain in electrical contact with the blood analysis part.
It will be appreciated that the maximum permissible height dimension of the electrical contact terminals 405 is determined by the height of the spacer member 308. A thicker spacer member allows larger electrical contact terminals 405 to be used. However, this is at the expense of an increase in separation between adjacent test disc members 208 to 210, and thus a reduced capacity for the cartridge 106. The use of electrical contact terminals 405 including a horizontal arm 405a and a depending contact head 405b allows the height dimension of the electrical contact terminals to be minimised whilst allowing good electrical contact between the electrical contact terminals and the contact pads 318 and also allowing the electrical contact terminals 405 to operate correctly over a sufficient number of cycles.
Referring now to
As shown in
A plunger arrangement 500 comprising a plunging arm 501 and a plunging head 502 is provided adjacent a plunging aperture (not shown) in the hollow cylindrical housing part 203. The plunging aperture (not shown) is located next to the slit aperture 400. The plunging aperture (not shown) is located directly opposite to the aperture 105. The plunger aperture and the slit aperture 400 may be combined to form a single aperture. The plunger aperture is configured to allow the plunging head 502 to be forced by the plunging arm 501 to a position internal to the hollow cylindrical housing part 203.
Within the cartridge 106 are plural test disc members, one of which is shown as 505 in
A lancet 506 is provided extending from the disc edge 305 in the cutaway portion 302. In particular, the lancet 506 extends in a radial direction with respect to the centre of the test disc member 505. The lancet 506 extends from a fourth position 507, which is near to the second position 313. The fourth position 507 is further from the second position 313 than is the corresponding first position 312 in the embodiments described above. However, because the lancet 506 is radial with respect to test disc member 505, a distal end 506A of the lancet 506, i.e. the end that is furthest from the centre of the test disc member 505, is at approximately the same position as the corresponding end of the lancet 309.
The majority of the test disc member 505 is substantially rigid. However, an annular centre portion 508 is comprised of an elastically deformable material. In particular, the annular centre position 508 is deformable in the presence of an externally applied force. This means that the test disc member 505 can be displaced relative to the shaft 204, as will be described in more detail below. The material used to form the annular centre portion 508 may take any suitable form, and for instance may be a rubberised plastic.
In
In
Displacement of the test disc member 505 in the direction of the force supplied by the plunger arrangement 500 has resulted in displacement of the lancet 506 in a radial direction away from the shaft 204. In this position, the lancet 506 penetrates the skin of the user's digit. Removal of the force by the plunger arrangement 500 allows the annular centre portion 508 to return to its original form, through elastic reformation. After the plunger arrangement 500 has been fully retracted, the arrangement again has the form shown in
After removal of the force supplied by the plunger arrangement 500, the test disc member 505 can be rotated by the drive wheel 201 and the drive belt 202 so as to provide milking of the user's digit and then collection of blood at the blood collection portion 315, which position is shown in
An advantage of the arrangement shown in
Another advantage is that the arrangement can allow the penetration depth of the lancet 506 to be easily predictable.
Furthermore, it allows the penetration or puncturing depth to be adjustable. In particular, the adjustment of the penetration depth can be achieved by a mechanical arrangement that limits movement of the plunger arrangement towards the shaft 204. Alternatively, it can be achieved in an electro-mechanical manner by measuring the location or displacement of some part of the mechanism and ceasing applying an energising voltage to a solenoid or other transducer that is used to affect movement of the plunger arrangement 500. Penetration depth control is important to many users since lancet penetration usually is painful and since penetration depth control allows users some control over their experience.
An alternative form of test disc member 600 is shown in
The test disc member 600 differs from the test disc member 208 shown in
At the part of the curved lancet 601 that is adjacent the disc edge 305, the longitudinal axis of the curved lancet 601 is at an angle X with respect to a straight line drawn between the junction between the curved lancet 601 and the disc edge 305 and the centre of the shaft 204. The curve of the curved lancet 601 is such that the longitudinal axis of the curved lancet at the end distant from the disc edge 305 is at an angle greater than the angle X with respect to the line drawn between the junction between the curved lancet 601 and the disc edge 305 and the centre of the shaft 204. The effect is that the curved lancet 601 is more aligned with the circumference of the test disc member 600 at its distal end than it is at the end that adjoins the disc edge 305. This has the positive effect that when the lancet penetrates a user's digit, or other body part, due to rotation of the test disc member 600, the path taken by the lancet as it penetrates the user's digit more closely matches the shape and orientation of the lancet than is experienced in a corresponding arrangement with a straight lancet.
This effect is enhanced with the lancet 601 since the cylindrical form of the lancet 601 is terminated at the distal end by an oblique cut. In particular, the distal end of the curved lancet 601 resembles a cylinder that has been cut at an angle that is not perpendicular to the longitudinal axis of the cylinder. As such, the end face of the curved lancet 601 has the shape of an ellipse. The ellipse has a semi-major axis and a semi-minor axis and the point that is at the end of the semi-major axis that is furthest from the disc edge 305 forms a point. The cut is made through the lancet 601 such that the point is formed extending in a direction that is substantially circumferential with respect to the test disc member 600.
The configuration of the test disc members 208 to 210, 505, 600 is such that operation results in milking of the puncture in the user's digit caused by the lancet 309. In particular, the aperture 105 is configured such as to allow an amount of the flesh making up the end of the user's digit to be present within the internal volume of the cylindrical part 203 when the user presses the digit up against the aperture 105. When the user applies force into the aperture 105 with the digit, the digit distorts and a bulbous part is provided within the internal diameter of the hollow cylindrical housing part 203. The size of the bulbous part, and in particular the height of the bulbous part, depends on a number of factors, including the physical characteristics of the user's digit and the amount of force that the user applies, as well as the configuration of the aperture 105.
The aperture 105 is dimensioned such that in normal use (i.e. with a typical user applying a typical amount of force) a bulbous part of the user's digit extends into the internal volume of the hollow cylindrical housing part 203 to a depth of approximately 1 millimetre. The test disc members 208 to 210, 505, 600 are configured to have a cutaway portion 302 that is shaped such that when the lancet 309 is at a position at which it can lance the user's digit, the disc edge 305 is not in contact with the user's digit (i.e. the separation between the disc edge 305 and the aperture 105 is greater than 1 mm). This part of the cutaway portion 302 can be termed a first milking portion. At this position, the pressure exerted by the user results in the fluid pressure within the bulbous part of their digit being slightly greater than normal pressure. The increased pressure results from the force the user applies to their digit. This pressure encourages bleeding of the puncture that is caused by the lancet 309. Advantageously, the arrangement of the relevant features is such that the lancet 309 penetrates the user's digit to a depth of between 0.4 and 0.7 millimetres.
As the test disc member 208 to 210, 505, 600 then rotates anticlockwise, the lancet 309 is removed from the user's digit. A short time thereafter, the end of the bulbous part of the user's digit comes into contact with the disc edge 305 at a position approximately one-third to two-fifths of the way along the cut out portion 203. This part can be termed the second milking portion. The test disc member 208 to 210, 505, 600 has a substantially constant radius for the second milking portion, which extends to a position approximately two-thirds or four-fifths of the way along the cutaway portion 302. For the time at which the second milking portion is coincident with the bulbous part of the user's digit as the test disc member 208 to 210, 505 rotates, the internal pressure of the bulbous part of the user's digit is increased compared to the time at which the user's digit was in contact with the lancet 309. Furthermore, as the disc edge 305 moves into contact with and over the bulbous part of the digit, blood under the skin is caused to be pushed towards the puncture caused by the lancet.
Between the second milking part and the location of the blood collection part 315, the radius of the test disc member 208 to 210, 505, 600 is reduced, or put another way has a lower value. This portion can be termed a third milking portion. As such, after the second milking portion and before the user's digit contacts the blood collection part 315, the pressure applied to the bulbous part of the user's digit by the disc edge 305 is reduced compared to the pressure applied at the second milking portion. Advantageously, the radius of the test disc member 208 to 210, 505, 600 at the third milking portion is selected such that the bulbous part of the user's digit does not contact the disc edge 305 (i.e. the separation between the disc edge 305 and the aperture 105 is greater than 1 mm). Whilst the third milking portion is coincident with the user's digit as the test disc member 208 to 210, 505, 600 rotates, blood is free to exit the puncture made by the lancet 309. As the test disc member 208 to 210, 505, 600 continues to rotate, the disc edge 305 again contacts the bulbous part of the user's digit at a location just before the blood collection portion 315. This again increases the internal pressure within the bulbous part of the user's digit. This encourages the movement of blood towards the analyte measuring part 316. The separation between the disc edge 305 at the location of the blood collection portion 315 and the aperture 105 is approximately 0.5 mm.
The configuration of the test disc members 208 to 210, 505, 600 thus encourages milking of a sample of blood from the user's digit. The sequence is as follows: Firstly, lancing by the lancet 309 with a relatively low pressure (caused by no contact with the disc edge 305 and the user's digit), followed by a period for which relatively low amount of pressure, as well as a rubbing movement, is provided by the second milking portion to the user's digit, followed by a period for which little or no pressure is provided by the disc edge 305 against the user's digit, followed by a relatively high pressure provided by the disc edge 305 against the user's digit just before and at the blood collection part 315.
Operation of the blood glucose meter 100 will now be described with reference to the flowchart of
At step S7, the software/firmware causes the microprocessor 212 to control the motor to cease rotation when the shaft 214 is such that the blood collection member 315 is coincident with the aperture 105, and thus the user's digit. At step S8, the software/firmware controls a motor such as to cause the swing arm 401 to be rotated towards the shaft 204. The software/firmware stored in the ROM 214 is such that the microprocessor 212 causes only the required amount of travel of the swing arm 401. At this point, the analyte interface circuit 219 is coupled directly to the blood analyte measuring part 316, which by action of the blood collection part 315 has been provided with blood from the user's digit. At step S9, analyte measurement is performed. This involves the analyte interface circuit 219 providing voltages to the electrical connection contacts 318, and thus to the blood analyte measuring part 316, and measuring parameters of resulting signals. The measured parameters, particularly voltage parameters, are used by the software/firmware stored in the ROM 214, as executed by the processor 212, to calculate a blood glucose measurement level of the user. The blood glucose measurement is then caused by the software/firmware to be displayed on the display 104 through action of the microprocessor 212 on the display drive 216. At step S10, the swing arm is caused to be removed by action of the microprocessor 212, under control of the software stored in the ROM 214, the motor interface 217 and the motor (not shown).
At step S11, the software/firmware results in the microprocessor 212 controlling the drive disc 201 to rotate anticlockwise. Rotation continues until the notch 301 on the test disc member is coincident with the guide 206. At step S12, the test disc member rises up the cartridge 106. In the case where biasing of the test discs up the cartridge 106 is provided by a bias means, for instance a spring, step S12 requires no action on part of the software/firmware and microprocessor 212, although there may be a pause before the next step. In embodiments where movement of the test disc members along the shaft 204 occurs through driving action, step S12 involves the microprocessor 212, under control of the software/firmware stored in the ROM 214, controlling a motor through the motor interface 217. Subsequently, at step S13, the microprocessor 212, under control of the software/firmware stored in the ROM 214, causes the shaft 204 to rotate again in a clockwise direction and to cease rotating when the drive dog 320 engages with the drive slot 307 of the next test disc member in the cartridge 106. At this stage, the test disc members rise up the cartridge 106 slightly.
The operation ends at step S14.
Operation starts at step T1. At step T2, the user locates their digit in the aperture 105. As mentioned above, the user forces their digit into the aperture 105 with a pressure or force that is suitable to allow lancing and blood collection. At step T3, the user initiates blood glucose measurement. This involves the user pressing one of the inputs 101 to 103. This is detected by the microprocessor 212 by way of the keys interface 215. The software/firmware stored in the ROM 214 uses the key input to call a function or to execute a software module. The software/firmware stored in the ROM 214 then causes the microprocessor 212 to issue a command to a motor attached to the drive wheel 201 through the motor interface 217 to rotate the shaft 204 in a clockwise direction. The software/firmware controls the extent of the rotation.
Following step T3, the microprocessor 212, under control of the software/firmware stored in the ROM 214, causes the shaft 204 to be rotated by a motor through the motor interface 217 and to cease rotation once the lancet 508 is aligned with the aperture 105, and thus is aligned with the user's digit, at step T4A. At step T4B, the microprocessor 212, under control of the software/firmware stored in the ROM 214, causes actuation of the plunger arrangement 500, through the motor interface 217. The control of the actuation of the plunger is such as to limit the extent of movement of the lancet 508 to a predetermined extent. The predetermined extent is set by a user through operation of the keys 102, 103 prior to the blood glucose measurement. In effect, the user can use the keys 102, 103 to set a lancing depth, which is stored in a suitable way in the ROM 214 by action of the microprocessor 212, operating under control of the software/firmware stored in the ROM 214.
When the maximum extent of plunger actuation has been reached at step T4B, at step T4C the plunger arrangement 500 is deactuated by the microprocessor 212, under control of the software/firmware stored in the ROM 214, and lancing ceases. At this step, the test disc member returns to its original position by action of the elasticity of the annular centre portion 508 of the test disc member 508.
Although in the figures, an in particular in
The software/firmware stored in the ROM 214 then causes the microprocessor 212 to control the motor to rotate the shaft 204 in the opposite direction, at step T5. As the test disc member rotates anticlockwise, milking occurs at step T6. Firstly, at step T6A, there is no pressure applied by the test disc member on the digit. At step T6B, there is a medium amount of pressure on the digit. At step T6C, there is low or no pressure applied by the test disc member on the digit. At this point, the digit coincides with the part of the test disc member that is immediately before the blood collection part 315.
At step T7, the software/firmware causes the microprocessor 212 to control the motor to cease rotation when the shaft 214 is such that the blood collection member 315 is coincident with the aperture 105, and thus the user's digit. At step T8, the software/firmware controls a motor such as to cause the swing arm 401 to be rotated towards the shaft 204. The software/firmware stored in the ROM 214 is such that the microprocessor 212 causes only the required amount of travel of the swing arm 401. At this point, the analyte interface circuit 219 is coupled directly to the blood analyte measuring part 316, which by action of the blood collection part 315 has been provided with blood from the user's digit. At step T9, analyte measurement is performed. This involves the analyte interface circuit 219 providing voltages to the electrical connection contacts 318, and thus to the blood analyte measuring part 316, and measuring parameters of resulting signals. The measured parameters, particularly voltage parameters, are used by the software/firmware stored in the ROM 214, as executed by the processor 212, to calculate a blood glucose measurement level of the user. The blood glucose measurement is then caused by the software/firmware to be displayed on the display 104 through action of the microprocessor 212 on the display drive 216. At step T10, the swing arm is caused to be removed by action of the microprocessor 212, under control of the software stored in the ROM 214, the motor interface 217 and the motor (not shown).
At step T11, the software/firmware results in the microprocessor 212 controlling the drive disc 201 to rotate anticlockwise. Rotation continues until the notch 301 on the test disc member is coincident with the guide 206. At step T12, the test disc member rises up the cartridge 106. In the case where biasing of the test discs up the cartridge 106 is provided by a bias means, for instance a spring, step T12 requires no action on part of the software/firmware and microprocessor 212, although there may be a pause before the next step. In embodiments where movement of the test disc members along the shaft 204 occurs through driving action, step T12 involves the microprocessor 212, under control of the software/firmware stored in the ROM 214, controlling a motor through the motor interface 217. Subsequently, at step T13, the microprocessor 212, under control of the software/firmware stored in the ROM 214, causes the shaft 204 to rotate again in a clockwise direction and to cease rotating when the drive dog 320 engages with the drive slot 307 of the next test disc member in the cartridge 106. At this stage, the test disc members rise up the cartridge 106 slightly.
The operation ends at step T14.
Instead of the blood collection part 315 being located next to the third position 314, i.e. bounding only the part of the disc edge 305 that is purely circumferential, the blood collection part could instead be located on the disc edge 305 at the junction between the cutaway portion 302 and the circumferential portion. The blood collection 315 part in this instance may extend for between 0.5 mm and 2 mm along the disc edge 305 at the cutaway portion 302. The blood collection 315 part in this instance may also extend for between 0.5 mm and 2 mm along the disc edge 305 at the circumferential part.
Alternatively or additionally, the analyte measuring part 316 may be sandwiched between two layers of wicking material, the wicking material causing the blood to be drawn through the analyte measuring part 316.
Although in the above the shaft 204 is said to be driven by a drive wheel 201 that is coupled to the shaft 204 by a drive belt 202, the drive may instead be direct (i.e. the drive mechanism is coupled directly to the shaft 204), or connection may be made by a notched belt, a vee belt, or by a direct gear mechanism. Instead of an electric motor, a clockwork drive could be used. A clockwork drive mechanism has a number of advantages, particularly where access to batteries or battery chargers or electricity supplies are limited. In the embodiments in which a clockwork mechanism is used, the user can be sure that the BGM 100 will not cease operating because of drained batteries. A clockwork mechanism may be particularly suited to developing countries and emerging markets.
In embodiments in which an electrical motor is used to drive the shaft 204, preferably control is exerted over the motor by software. In this way, the speed of rotation can easily be controlled. Additionally, the extent of rotation can more easily be controlled. The motor may be a stepper motor.
Alternatively, a mechanical drive arrangement may be present, for instance using a lever or other device for manual actuation. A suitable mechanism may be one similar to those previously used in SLR cameras.
The swing arm 401 may be actuated in any suitable way. For instance, it may be driven by the same motor or mechanism as the shaft 204. Alternatively, it may be driven by a separate motor. In either case, the rotation of the swing arm 404 may be affected by a cam mechanism, or by a pin and slot (track path) mechanism. In the event of an electric motor being used, the motor preferably is software driven. The motor preferably is a stepper motor.
The mechanical arrangement may include a mechanism by which a bias means, for instance a mechanical compression spring, is biased and then released in order to push the electrical contact terminals 405 into place. The terminals 405 can then be retracted by the swing arm 401 using a rotating motion. The overall mechanism can be termed a latch type trigger mechanism.
Instead of a swing arm 401 being used to rotate the electrical contact terminals 405 into place, the contact pads 318 may instead be located on the disc edge 305, allowing the use of fixed electrical contact terminals 405. The electrical contact terminals may include a brush or other deformable feature such that the test disc members 208 to 210, 505, 600 can move whilst in contact with the electrical contact terminals without damage occurring to any of the components. Similar arrangements are used in brushed DC motors. In this case the electrical contact terminals 405 could be flexible finger contacts that rest on the periphery of the test disc members 208 to 210, 505, 600 in order to contact the contact pads 308.
Alternatively, instead of a swing arm 401, a mechanism may be used to affect longitudinal movement of the electrical contact terminals 405 into place to contact the contact pads 318.
The conductive tracks 317 and the contact pads 318 may be formed by leadframe. Alternatively, overmoulding may be used. Alternatively, printed circuit board (PCB) printing may be used.
Optionally, each of the test disc members 209, 210, 505, 600 is separated from adjacent test disc members by a membrane (not shown in the drawings). In this case, the membrane preferably fits closely to the internal surface of the hollow cylindrical housing part 203. An effect of the membrane is to reduce the possibility of disc cross-contamination. Use of a membrane may allow the test disc members 208 to 210, 505, 600 to have a reduced separation than would be the case without the use of a membrane.
In the above, the test disc members 208 to 210, 505, 600 are said to be biased upwards by a bias means, for instance a compression spring. Alternative mechanisms for moving the test disc members 208 to 210, 505, 600 up the cartridge may be used. For instance, a threaded lifting cam may be provided on the shaft 204 or alternatively on the interior surface of the hollow cylindrical housing part 203. Alternatively, the test disc members 208 to 210, 505, 600 may remain stationary, with the aperture 105 and the drive dog 320 instead being moved along the axis of the cartridge 106. Movement of the aperture 105 may be achieved by the use of a sliding door in an elongated slot. Movement of the door allows a different strip to be revealed at the aperture 105.
Instead of the blood collection portion 315 wicking blood towards the analyte measuring part 316, blood may be communicated to the analyte measuring part 316 instead through gravity.
Additionally, the test disc members 208 to 210, 505, 600 may include a disinfecting or cleaning portion that contacts the digit before lancing. This can reduce risk of infection of the wound and also can increase accuracy in particular by removing any glucose from the skin (as may occur after eating fruit etc.).
Additionally or alternatively, the test disc members 208 to 210, 505, 600 may include a cleaning portion that is arranged to contact the digit subsequent to the blood collection part 305. This can remove additional blood from the finger, and may also serve to assist closure of the puncture.
The device described thusfar is also described in PCT/EP2011/061536.
Although not shown in
As best seen in
A main face of the seal 702 is in close contact with an outside surface of a side wall of the cartridge 106 when the seal 702 is in place. This is best seen in
When the seal 702 is in the sealed position, in which it covers the aperture 105, it is secured to the exterior side wall of the cartridge 106. The seal 702 may be secured by a non-permanent adhesive. The adhesive may be provided all the way around the circumference of the aperture 105, thereby resulting in a moisture seal to prevent the ingress of moisture from the exterior of the cartridge 106 to the interior through the aperture 105. The seal 702 may be absent of adhesive other than in the immediate vicinity of the aperture 105. The seal 702 may be affixed directly to the cartridge only by the non-permanent adhesive.
The aperture 105 is covered when the seal is in place by one end of the seal 702. At the other end of the seal 702 is fixed a knob 701. The knob 701 is a moulded plastic component. The knob 701 is secured to the seal 702 in any suitable way. As will be appreciated from the below explanation, the knob 701 is secured to the seal 702 sufficiently to allow the force needed to overcome the stiction of the adhesive when separating the seal 702 from the exterior surface of the cartridge 106.
A protrusion 703 is formed on the cartridge 106. The protrusion 703 is located on the side wall of the cartridge 106. The protrusion 703 is located at the end of the cartridge 106, so is at the junction between the end face 707 and the side wall of the cartridge 106. As can be seen most clearly from
The protrusion 703 has a height, in the radial distance from the longitudinal axis of the cartridge 106, of a few millimetres, for instance between 1 and 5 millimetres. The protrusion 703 has a length, parallel to the longitudinal axis of the cartridge 106, of a few millimetres, for instance between 2 and 8 millimetres.
The protrusion 703 serves as a guiding member. The protrusion 703 cooperates with a groove 708 that is formed on an inside surface of the part of the BGM 100 that receives the cartridge in use.
The groove 708 is shown in
The longitudinal axis of the groove 708 in the interior part of the BGM 100 is parallel to the longitudinal axis of the bore thereof, and thus has the same axis as the protrusion 703.
The knob 701 has a groove 704 formed in a face thereof. The groove 704 is formed in the face of the knob 701 that faces the side wall of the cartridge 106 when the seal 702 is in the sealing position. The groove 704 within the knob 701 has a cross-section corresponding to the cross-section of the protrusion 703. The position of the knob 701 when the seal 702 is adhered to the side wall of the cartridge 106 in the sealed position is such that the protrusion 703 is received in the groove 704 in the knob 701. This is best seen in
The length of the groove 704 may be greater than the length of the protrusion 703, or it may be the same length as the protrusion 703. The groove 704 may taper from the end furthest from the end of the seal 702 that covers the aperture 105 such that it has less depth (is shallower) at locations closest to the aperture 105. If a taper is present, the taper starts off parallel with the side of the cartridge and tapers a gentle angle at first. Starting the taper tangentially helps to achieve smooth operation.
When the seal 702 is sealed to the side wall of the cartridge 106, a face of the knob 701 that is furthest from the aperture 105 is substantially level with the plane of the end face 707 of the cartridge 106. This face may be in the same plane as the end face 707. This provides a convenient profile for the cartridge 106 and allows easy operation, as is described below.
The knob 701 may be highly visible. For instance, the knob 701 may be formed of a brightly coloured material, such as plastic.
When the seal 702 is in the sealed position over the aperture 105, the knob 701 is engaged with the protrusion 703.
The knob 701 and the cartridge 106 may be connected together by a temporary fixing. The temporary fixing may be formed by plastics moulding. For instance, the knob 701 and the cartridge 106 may be moulded at the same time so as to provide a breakable rib between the two components. The temporary fixing has the effect of maintaining the knob 701 in position on top of the protrusion 703 when the seal 702 is in the sealed position whilst allowing a user to be able to separate the knob 701 from the protrusion 703, and thus separate the seal 702 from the aperture 105, when required.
When the knob 701 is in place over the protrusion 703, the material of the knob 701 in effect adds to the diameter of the cartridge 106. The increase in diameter is relatively small at the position of the tip of the protrusion 703, and is greater at locations either side of the tip of the protrusion 703. An effect of this is that, when the knob 701 is in place on the protrusion 703, the presence of the knob 701 prevents the cartridge 106 from being insertable into the BGM 100. In particular, the presence of the knob 701 prevents the protrusion 703 from engaging within the groove 708 in the interior surface of the BGM 100. As such, the cartridge 106 cannot be inserted into the BGM 100 until the knob 701, and thus the seal 702, has been removed. Because the presence of the seal 702 over the aperture 105 during operation of the BGM could cause damage to one or more components thereof, this reduces the possibility of damage occurring through failure to remove the seal 702 prior to use.
The knob 701 includes a sloped face 705 that is opposite to the face that is furthest from the end of the seal 702 that covers the aperture 105. The sloped face 705 of the knob 701 is sloped downwards from the highest part of the knob 701, in the sense that it is highest in a radial direction from the longitudinal axis of the cartridge 106, downwards in a direction towards the aperture 105. Furthermore, the face 105 of the sloped knob 701 is curved such that the gradient of the face is steeper for a greater radial distance and becomes less steep for smaller radial distances from the longitudinal axis of the cartridge 106. This provides a convenient surface against which a user can exert a force in a direction parallel to the longitudinal axis of the cartridge 106, for instance using their thumb.
Removal of the seal 702 by a user will now be described, primarily with reference to
The starting position is with the seal 702 in place over the aperture 105 and the knob 701 in place over the protrusion 703. This is illustrated by the position of the rightmost knob 701 in
The user then has two main options for manipulating the knob 701 so as to remove the seal 702.
The first involves the user grasping the cartridge 106 within the palm of their hand, for instance the hand shown on the right side of
The direction in which the knob 701 moves is set by the interoperation between the protrusion 703 and the groove 704 in the knob. The continued presence of the protrusion 703 within the groove 704 is ensured by the nature of the arrangement because the user necessarily will exert a force on the knob 701 towards the longitudinal axis of the cartridge 106 (downwards in
Once the knob 701 has moved sufficiently that the temporary adhesive seal between the seal 702 and the exterior side wall of the cartridge 106 has been broken, the seal 702 and the knob 701 are no longer affixed to the cartridge 106. At this position, the knob 701 and the seal 702 can be removed, and the result is the cartridge shown in
An alternative way in which a user can manipulate the knob 701 will now be described. Starting with the seal 702 in the sealed position over the aperture 105 and the knob 701 located over the protrusion 703, a user may grasp the knob 701 with a hand different to a hand that is grasping the cartridge 106. Here, a user may grasp the knob 701 between their finger and their thumb, with one of these digits being located against the face 705 and the other being at least partly in contact with the face that is furthest from the aperture 105. Optionally using leverage by providing a force against the end face 707 of the cartridge 106, a user may pull the knob 701 in a direction away from the aperture 105. The remaining part of the operation is as described above in relation to the alternative manner in which the user can manipulate the knob 701.
The presence of the seal 702 over the aperture 105 can protect the testing members inside the cartridge 106 from moisture, dust, reactive gases (like sulphur dioxide), and bacteria during storage prior to use.
The arrangement of the embodiments described above can prevent the cartridge 106 being inserted into the BGM 100 prior to removal of the seal 702. In other words, the cartridge 106 can only be inserted into the BGM 100 once the user has removed the seal 702 and the knob 701.
The cooperation between the protrusion 703 and the groove 704 of the knob 701 assists the user when removing the seal 702. Furthermore, the presence of the protrusion 703 on the side wall of the cartridge 106 after the seal 702 and the knob 701 have been removed allow correct orientation of the cartridge 106 within the BGM 100, by virtue of cooperation between the protrusion 703 and the groove 708.
Once all of the testing members within the cartridge 106 have been used, the cartridge 106 can be removed from the BGM 100 and discarded or sent for re-use. At this stage, a seal 702 from a new cartridge 106 can be removed and the cartridge 106 then inserted into the BGM 100.
Number | Date | Country | Kind |
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12150616.6 | Jan 2012 | EP | regional |
The present application is a U.S. National Phase Application pursuant to 35 U.S.C. §371 of International Application No. PCT/EP2013/050307 filed Jan. 9, 2013, which claims priority to European Patent Application No. 12150616.6 filed Jan. 10, 2012. The entire disclosure contents of these applications are herewith incorporated by reference into the present application.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2013/050307 | 1/9/2013 | WO | 00 |